hm-sa-skill

name

hm-sa-skill

description

HarmonyOS/OpenHarmony System Ability Manager (SAMgr) daemon domain expertise. Covers SA architecture, lifecycle management, IPC/RPC communication patterns, service registration/discovery, source code structure, and API reference. Use when: (1) Working with OpenHarmony SAMgr / systemabilitymgr_samgr code, (2) Questions about SA lifecycle, daemon startup, or boot sequence, (3) Implementing or debugging IPC/RPC Proxy/Stub patterns for system services, (4) Understanding SA registration (AddSystemAbility, GetSystemAbility, LoadSystemAbility), (5) Analyzing SAMgr crash recovery, on-demand loading, or distributed SA routing, (6) Navigating the systemabilitymgr subsystem source tree.

HarmonyOS System Ability Manager (SAMgr) Skill

Overview

SAMgr is the daemon-level service registry and lifecycle manager for all system services in HarmonyOS/OpenHarmony. It plays a role analogous to Android's servicemanager + init daemon, with stronger lifecycle governance and native cross-device distributed support.

Knowledge Domains

This skill covers four domains. Load the relevant reference file based on the task:

Domain	Reference	When to Load
Architecture & Concepts	references/hm-sa-architecture.md	Understanding SAMgr's role, boot sequence, SA lifecycle, data structures, registration modes
API Reference	references/hm-sa-api-reference.md	Writing SA code, Proxy/Stub patterns, registration macros, death notifications
Source Code Structure	references/hm-sa-source-structure.md	Navigating the repo, finding files, understanding build config, SA .cfg format

Quick Reference

SAMgr's Four Roles

1. Service Registry — Central table mapping SA ID → proxy object
2. Lifecycle Manager — OnStart/OnStop, crash detection, auto-restart
3. IPC Router — Local via Binder, cross-device via DSoftBus
4. Capability Scheduler — Boot ordering, priority, on-demand loading

SA Lifecycle

Register → Publish → Discovery → IPC Invocation → Reclamation

Core API (C++)

// Get SAMgr client
sptr<ISystemAbilityManager> samgr =
    SystemAbilityManagerClient::GetInstance().GetSystemAbilityManager();

// Register SA
samgr->AddSystemAbility(saId, new MyAbility());

// Get SA proxy
sptr<IRemoteObject> obj = samgr->GetSystemAbility(saId);

Boot Sequence

init → parse .cfg → SAMgr daemon → foundation (safwk + samgr) → appspawn → apps

Source Repo

• GitHub: https://gitcode.com/openharmony/systemabilitymgr_samgr
• Path: foundation/systemabilitymgr/samgr/

Fetching Official Docs

To refresh the fetched Huawei developer docs, run:

# Fetch IPC Kit docs (preset)
python3 scripts/fetch_sa_docs.py --preset ipc --out-dir references/fetched-docs

# Fetch a single doc by slug
python3 scripts/fetch_sa_docs.py --slug ipc-rpc-overview --out /tmp/doc.md

# List all known working slugs
python3 scripts/fetch_sa_docs.py --list-slugs

Known working slugs:

• ipc-rpc-overview — IPC Kit V13 overview (current)
• ipc-rpc-overview-0000001427584740-V2 — IPC RPC V2 overview (archived)

Key Comparison: Android vs HarmonyOS

Dimension	Android	HarmonyOS SAMgr
Service Management	Dispersed (app-driven)	Unified (system-driven)
Lifecycle	App-controlled	System-controlled
Cross-device	None built-in	Natively supported
Crash Recovery	Limited	Auto-restart + client notification

Recognized SA IDs

SA ID	Service
3001	PowerManager
3002	LocationService
3400	BundleMgrService